Many old, gigantic trees around the world are slowly becoming endangered, just like some species of lions, tigers and whales, said researchers.

The researchers said the main causes of the loss of old trees are logging, land clearing, forest fires and heavy use of lands for farming and food production.

The problem was not given much attention until a new study by Australian and American researchers. Australian National University ecologist David Lindenmayer and colleagues worked together to document the decline of old and large trees in different countries.

The decline in some forests, such as in the forests in Victoria, Australia, have already been well-studied. Only one percent of Victoria’s forests are still made up of big, old trees, some of which have been alive since the 1700s. Lindenmayer forecasts that by 2070, Victoria’s forests will decrease to 0.6 trees per hectare.

However, researchers learned the decline is happening all over the world. The decline has been observed in many environments—in the tropical forests of Asia, South and Central America; in the cities of Europe and in the savannahs of southern Africa.

Between the 1930s and 1990s, California's Yosemite National Park experienced a 24% decline in gigantic trees. Meanwhile, in southern Sweden, trees with diameters measuring 45 centimeters or more have decreased from about 19 trees per hectare to only around one tree per hectare.

Lindenmayer said the decline in big, old trees would also reduce wildlife that uses the trees as homes. The loss of these trees also greatly changes the environment of an area.

Viewpoint Discussion Enjoy a discussion with your tutor.
Discussion A

·Do you think saving plants or trees is as important as saving animal species? Why or why not?

·How do you think we can encourage people to care more about forests and trees?